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v3.25.3

Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jul. 31, 2025 USD ($) | Jul. 31, 2025 JPY (¥) | Jun. 30, 2025 USD ($) | Apr. 30, 2025 USD ($) | Apr. 30, 2025 JPY (¥) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 JPY (¥) | Sep. 30, 2025 EUR (€) | Sep. 30, 2025 GBP (£) | Dec. 31, 2024 USD ($)
Berkshire Hathaway Inc. (Parent) [Member] | Berkshire Hathaway Finance Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Notes payable and other borrowings |  |  |  |  |  |  |  |  |  | ¥ 2,188.0 | € 4,850 | £ 1,750 |
Line of Credit and Commercial Paper Facilities [Member] | Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Unused and available lines of credit |  |  |  |  |  | $ 10,900 |  | $ 10,900 |  |  |  |  |
Line of Credit and Commercial Paper Facilities [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy and Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Unused and available lines of credit |  |  |  |  |  | 9,900 |  | 9,900 |  |  |  |  |
Insurance and Other [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Notes payable and other borrowings |  |  |  |  |  | 45,617 |  | 45,617 |  |  |  |  | $ 44,885
Insurance and Other [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Guarantee obligation |  |  |  |  |  | 1,700 |  | 1,700 |  |  |  |  |
Insurance and Other [Member] | Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term borrowings |  |  |  |  |  | $ 1,320 |  | $ 1,320 |  |  |  |  | 1,315
Weighted average interest rate, percentage |  |  |  |  |  | 5.10% |  | 5.10% |  | 5.10% | 5.10% | 5.10% |
Notes payable and other borrowings |  |  |  |  |  | $ 3,544 |  | $ 3,544 |  |  |  |  | 4,564
Insurance and Other [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of borrowings |  |  |  |  |  |  |  | 1,600 |  |  |  |  |
Insurance and Other [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Berkshire Hathaway Finance Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Gains (loss) attributable to changes in foreign currency exchange rates |  |  |  |  |  | 433 | $ (1,500) | $ (1,700) | $ (136) |  |  |  |
Insurance and Other [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2028 to 2055 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt issued |  |  |  | $ 632 | ¥ 90.0 |  |  |  |  |  |  |  |
Interest rate during period |  |  |  | 1.60% | 1.60% |  |  |  |  |  |  |  |
Insurance and Other [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2030 to 2040 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt issued | $ 1,000 | ¥ 151.5 |  |  |  |  |  |  |  |  |  |  |
Interest rate during period | 2.30% | 2.30% |  |  |  |  |  |  |  |  |  |  |
Insurance and Other [Member] | Minimum [Member] | Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  |  | 2025 |  |  |  |  |
Insurance and Other [Member] | Minimum [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2028 to 2055 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  | 2028 | 2028 |  |  |  |  |  |  |  |
Insurance and Other [Member] | Minimum [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2030 to 2040 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year | 2030 | 2030 |  |  |  |  |  |  |  |  |  |  |
Insurance and Other [Member] | Maximum [Member] | Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  |  | 2051 |  |  |  |  |
Insurance and Other [Member] | Maximum [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2028 to 2055 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  | 2055 | 2055 |  |  |  |  |  |  |  |
Insurance and Other [Member] | Maximum [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2030 to 2040 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year | 2040 | 2040 |  |  |  |  |  |  |  |  |  |  |
Railroad, Utilities and Energy [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Notes payable and other borrowings |  |  |  |  |  | 81,626 |  | $ 81,626 |  |  |  |  | 79,877
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy and Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term borrowings |  |  |  |  |  | $ 1,719 |  | $ 1,719 |  |  |  |  | 1,123
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate, percentage |  |  |  |  |  | 4.80% |  | 4.80% |  | 4.80% | 4.80% | 4.80% |
Notes payable and other borrowings |  |  |  |  |  | $ 44,943 |  | $ 44,943 |  |  |  |  | $ 42,150
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Term Debt [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of borrowings |  |  |  |  |  |  |  | 2,400 |  |  |  |  |
Short-term borrowings |  |  |  |  |  | $ 600 |  | 600 |  |  |  |  |
Principal amount of debt issued |  |  |  |  |  |  |  | $ 3,100 |  |  |  |  |
Weighted average interest rate, percentage |  |  |  |  |  | 6.40% |  | 6.40% |  | 6.40% | 6.40% | 6.40% |
Railroad, Utilities and Energy [Member] | Senior Unsecured Debentures [Member] | Subsidiaries [Member] | BNSF [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of borrowings |  |  |  |  |  |  |  | $ 900 |  |  |  |  |
Principal amount of debt issued |  |  | $ 900 |  |  |  |  |  |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  | 5.80% |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  | 2056 |  |  |  |  |  |  |  |  |  |
Railroad, Utilities and Energy [Member] | Minimum [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  |  | 2025 |  |  |  |  |
Railroad, Utilities and Energy [Member] | Minimum [Member] | Subsidiaries [Member] | Term Debt [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  |  | 2035 |  |  |  |  |
Railroad, Utilities and Energy [Member] | Maximum [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  |  | 2064 |  |  |  |  |
Railroad, Utilities and Energy [Member] | Maximum [Member] | Subsidiaries [Member] | Term Debt [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  |  | 2055 |  |  |  |  |

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